1. Field of the Invention
The present invention relates to a light-emitting element that emits light by current excitation, and more particularly relates to the structure of a layer thereof. Further, the present invention relates to a light-emitting device and an electronic device using the light-emitting element.
2. Description of the Related Art
A light-emitting element that has a layer including a luminescent material between a pair of electrodes is used for a pixel, a light source, or the like, and is provided in a light-emitting device such as a display device or a lighting device. In this light-emitting device, the reliability of the light-emitting element is closely related to the performance of the light-emitting device. For example, when a short circuit is caused between the electrodes of the light-emitting element, a display image is distorted, or light of insufficient intensity can emitted.
Therefore, the development of a light-emitting element that is less defective and is able to emit light with stability for a long period of time has been developed recently. For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 9-63771) discloses a technique of manufacturing a light-emitting element that operates at a lower driving voltage by using a metal oxide having a higher work function, such as molybdenum oxide, for an anode. In addition, the-light-emitting element has an improved lifetime.